title: NOX1 abet mesangial fibrogenesis via iNOS induction in diabetes.
abstract: Both NADPH oxidase (NOX) and inducible nitric oxide synthase (iNOS) are the main sources of reactive oxygen species in kidney. However, their interactions in oxidative stress and contributions to kidney fibrosis during diabetic nephropathy have not been studied. Human mesangial cells were treated with normal glucose (5.6 mmol/L), high glucose (30 mmol/L) in the presence or absence of AGE (200 mg/L). Protein expressions of NOX1, NOX2, NOX4, and iNOS were examined by immunoblotting. NOX was genetically silenced with specific RNAi to study the interactions between NOX and iNOS in diabetic milieu. Superoxide (O(·-)) and peroxynitrite (ONOO(·-)) productions were assessed by dihydroethidium and hydroxyphenyl fluorescein, respectively. Fibrotic factors were determined by biochemistry assay. Superoxide, peroxynitrite, TGF-β, and fibronectin productions as well as the protein expressions of NOX1, NOX2, NOX4, and iNOS were increased in the diabetic milieu (high glucose 30 mmol/L plus AGE 200 mg/L). However, abolishment of iNOS induction with 1400W or iNOS RNAi would restore peroxynitrite, TGF-β, and fibronectin productions completely to basal level and attenuate superoxide production. Moreover, NOX1 inhibition not only prevented iNOS induction but also abrogated changes consequent to iNOS induction such as mesangial fibrogenesis.
authors.affiliation: Department of Endocrinology, Renmin Hospital of Wuhan University, Jiefang RD 238, Wuhan, 430060, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Gao
authors.forename: Weilu
authors.initials: W
authors.lastname: Huang
authors.forename: Jing
authors.initials: J
authors.lastname: Li
mesh_terms: D003920:Diabetes Mellitus / Q000201:enzymology* / Q000473:pathology*; D004790:Enzyme Induction / Q000187:drug effects; D005355:Fibrosis; D055785:Gene Knockdown Techniques; D005947:Glucose / Q000494:pharmacology; D017127:Glycation End Products, Advanced / Q000494:pharmacology; D006801:Humans; D006943:Hyperglycemia / Q000201:enzymology / Q000473:pathology; D008562:Membrane Glycoproteins / Q000378:metabolism; D050527:Mesangial Cells / Q000187:drug effects / Q000201:enzymology* / Q000473:pathology*; D000074624:NADPH Oxidase 1; D000074662:NADPH Oxidase 2; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000096:biosynthesis*; D030421:Peroxynitrous Acid / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D017127:Glycation End Products, Advanced; D008562:Membrane Glycoproteins; D017382:Reactive Oxygen Species; D013481:Superoxides; D030421:Peroxynitrous Acid; D052247:Nitric Oxide Synthase Type II; C056558:CYBB protein, human; D000074624:NADPH Oxidase 1; D000074662:NADPH Oxidase 2; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases; C402799:NOX1 protein, human; C498910:NOX4 protein, human; D005947:Glucose